In the tracking and engagement of hostile air or space threats, the ability to estimate the target position and velocity with high accuracy is extremely important. Current tracking capabilities include the use of radar. However, additional, independent tracking sources are important for increased accuracy and tracking continuity. This is especially important in the case where the radar track is dropped or the radar track errors are too large to support accurate missile guidance.
Improved or alternative methods are desired for tracking and engaging hostile air or space threats.